Heating, ventilation, air conditioning and/or refrigeration systems are widely used to regulate the temperature of buildings and other facilities, such as residential homes, office buildings, storage facilities, and other structures where it is desired to heat or cool the facility. In such applications, it is important to ensure that the mechanical systems for heating or cooling the facility are properly maintained. Specifically, it is known that the operating efficiency of a HVAC/R system decreases dramatically with even a minimal lack of maintenance to the system. As the system's efficiency decreases, the capacity of the system to heat or cool the facility decreases. Moreover, as the operating efficiency and capacity of the HVAC/R system decrease, the cost of operating the HVAC/R system increases. Conversely, a properly maintained HVAC/R system provides benefits in terms of lower operating costs and a longer service life.
When HVAC/R systems are not operating efficiently, or when they fail, the result is often discomfort to the persons residing in or utilizing the facilities, or even damage to property or the spoilage of perishable goods, such as food stored in a refrigerated system. In many situations, the failure or loss of use of an HVAC/R system can be avoided if the owner or user is aware of the impending problem. Unfortunately, homeowners and other users are often unaware of the operating efficiency of their HVAC/R systems or the warning signs of an impending failure, and are generally unable to repair the HVAC/R system themselves.
Many newer HVAC/R systems have a certain amount of built-in self-diagnostic capability to detect problems that affect performance. They include LED indicators which provide fault codes, otherwise known as flash codes or diagnostic trouble codes, which indicate to the user or service technician whether a malfunction exists and the type of malfunction that exists. When a fault is detected, the computer will illuminate the flash code lamp, and some systems may also store the diagnostic trouble code in its memory. To understand trouble codes, one often needs a reference manual that explains what the numbers mean and the step-by-step diagnostic procedure for isolating the fault. On some systems, a scan tool must be plugged into the computer system to access and read the codes. Therefore, even in systems with available flash codes, it is often necessary to have a skilled service technician come out to the home to read or determine the exact meaning of these codes.
Accordingly, when a problem does occur with an HVAC/R system, a visit by a trained service technician is usually required. Generally, the technician must travel to the location of the HVAC/R system to inspect the system and determine the source of the problem. Moreover, since it is impractical for service technician to have on hand all of the various components that might be necessary to restore the HVAC/R system to proper working order, the service technician must usually travel to another location to retrieve the necessary parts and subsequently return to the work location to repair the HVAC/R system. In the worst case, a part may not be readily available and must be ordered, whereby the service technician must return at a later date, further delaying repair and inconveniencing the owner or user of the system. This is particularly troublesome for HVAC/R systems which are located in remote areas.
While various devices for monitoring the operation of HVAC/R systems have been proposed, there is still a need for improved monitoring systems, and in particular for improved remote monitoring of HVAC/R systems with flash code capabilities, as will be described in more detail below.